Thermal ablation performance of Cf-HfB2 composites with and without a C matrix deposited by CVI

Research output: Contribution to journalArticle

Authors

External organisations

  • Birmingham University

Abstract

Cf-HfB2-based composites have been produced using a vacuum impregnation route with half of the samples being further densified by the inclusion of a carbon matrix using CVI. Both composites, Cf-HfB2 and Cf-HfB2/C, were characterised by oxyacetylene torch testing to determine the effect of the carbon matrix on the thermo-ablative performance. The mass loss of the samples revealed what whilst the Cf-HfB2 samples performed slightly better when tested for 60 s due to the presence of a surface layer of HfB2 powder, the Cf-HfB2/C composites were significantly superior when tested at nearly 3000oC for 300 s. The reason is believed to be related to the fact that the molten hafnia formed during testing was more absorbed by the Cf-HfB2 samples, which remained very porous. It is the presence of the viscous molten hafnia that is believed to offer the protection in this system.

Details

Original languageEnglish
Pages (from-to)211-221
Number of pages11
JournalCeramic Transactions
Volume263
Publication statusPublished - 1 Jan 2018

Keywords

  • Carbon matrix, Chemical vapor infiltration, Gaseous phase, Thermal ablation